Greetings from Germany, I'm planning to use STI brembo 4 pots on my Subaru BRZ and have heard various rumors on why that might not be a good idea after all (differential bore on pistons constraining the way they need to be mounted which means bleeders and plugs need to be swapped (apparently a real pain)
Also when doing that, the caliper is sitting upside down from it's original position (STI compared to BRZ) and rumors say the internal fluid transfer will then be in the top and hard / impossible to get all air out of the system.
Has anyone ever taken the two halves of these calipers apart?
Does anyone know for sure where exactly in the caliper the internal fuild transfer bore is?
Would the use of an external fluid transfer pipe (like on Evo brembo calipers) solve the issue mentioned above?
Many thanks in advance for your help, guys.

Greetings from Germany, I'm planning to use STI brembo 4 pots on my Subaru BRZ and have heard various rumors on why that might not be a good idea after all (differential bore on pistons constraining the way they need to be mounted which means bleeders and plugs need to be swapped (apparently a real pain)
Also when doing that, the caliper is sitting upside down from it's original position (STI compared to BRZ) and rumors say the internal fluid transfer will then be in the top and hard / impossible to get all air out of the system.
Has anyone ever taken the two halves of these calipers apart?
Does anyone know for sure where exactly in the caliper the internal fuild transfer bore is?
Would the use of an external fluid transfer pipe (like on Evo brembo calipers) solve the issue mentioned above?
Many thanks in advance for your help, guys.

Hello Sir,

Although it may seem like a good idea to stick with OEM parts, in this case it wouldn't be ideal due to the modifications required to make this possible.

If you are planning on using the calipers from a 04-07 STI you are correct about having to flip the crossover tubes and bleeders due to your calipers being mounted in front of axle vs. the STI behind axle. Since your calipers have internal crossover tubes this wouldn't be possible.

We would highly recommend you save yourself some time and consider our 4 POT kit that was designed to be direct bolt on.

Hello, thanks for the quick reply. In Germany every car mod needs to be approved by a technical inspection authority called "TÜV" and if passed, the changes will be added to the car's papers. Easiest (and most affordable) way to pass this inspection is with pre-approval papers called "Teilegutachten" (technical component report) or by using OEM parts. Assuming your kit doesn't come with such papers, my options are pretty much limited to kits specifically designed for the german market (with according papers) or to stick with OEM parts.
Speaking of OEM parts, the japanese BRZ tS comes with black brembo STI labeled 4 pot brembos from the factory.
So you are saying these are not the same as the WRX STI black 4 pot brembos?
If so, how do you know? Have you taken calipers apart and can share with us where exactly the internal crossover tube is within the caliper?
You seem to have plenty of experience and I'd greatly appreciate if you could share some of these technical details with us.